Montana runtime: AA Eneloops vs stock Li-Ion cell

[dictum9]

Montana 650T:

 

Elementary math suggests that the stock Li-Ion battery rated at 2,000 mAh and 4.2V (full) results in 8400 Watt-hours, while 3 Eneloop AA NiMH cells, arguably the best rechargeable AA cell, stand at 2,000 mAh * 1.3V * 3 = 7800 Watt-hours.

 

My experience suggests that you get better runtime with Eneloops, or maybe my Li-Ion cell has lost some capacity. Can anyone substantiate this observation?

 

In actuality, some of this math is wrong, as the Eneloops drop very quickly to 1.2V (while being as high as 1.5V off the charger) and the Li-Ion cell is closer to 3.7V. Either way, it looks fairly equal on paper runtime-wise.

 

I realize of course that you get the best runtime via Lithium AA cells (Energizer), but that is also the most expensive option.

[BikinOn]

Can't comment on the Montana, but with my Oregon 600 I typically get another 1 1/2 to 2 hours from the Eneloop XX batteries.

[+ecanderson]

Capacity ratings can create some elusive targets. What's important to add to the equation is the discharge profile (curve of voltage vs. power consumed vs. time) and an idea of where the Montana unit cuts off operation based upon sensed available voltage. Then, as you say, there's the capacity of these cells and batteries after N number of charge cycles. All of them grow old after a while -- some more gracefully than others.

 

Lots of elements involved, and so a straightforward attempt at multiplication rarely tells the whole story.

 

Also, how have you been storing the lithium ion pack? Do you store it fully charged for extended periods of time? Lithium packs really hate that. For longer term storage, you'll want to store at about 50% of full charge, else you'll find life decreases even more rapidly.

[+Mineral2]

Can't comment on the Montana, but with my Oregon 600 I typically get another 1 1/2 to 2 hours from the Eneloop XX batteries.

 

This is good to know. I've thought about buying a set of XX for my Oregon 450 as they tend to provide about 9-10 hours of use. But if the XX only provide up to 2 hours of additional use at twice the cost, I'll just stick with the white Eneloops.

[+Walts Hunting]

I bought a spare when I first got mine but have rarely needed it except on really long days. Didn't see a need to get a seperate system of batteries and charger. Especially since I am on the road six months a year.

Edited March 27, 2014 by Walts Hunting

[BikinOn]

This is good to know. I've thought about buying a set of XX for my Oregon 450 as they tend to provide about 9-10 hours of use. But if the XX only provide up to 2 hours of additional use at twice the cost, I'll just stick with the white Eneloops.

Well they say time is money, but most of us would regard a 4 Hours X 500 to be well worth an extra $5 for a pack of 4

[dictum9]

Re: Eneloop XX - it seems they gained runtime (capacity) at the expense of recharge cycles. The lower the capacity, the longer it stays good, and the lower is the self-discharge rate.

 

The higher capacity AA NiMH cells are great if you constantly use them.

About 6 years ago, I got both Maha Powerex 2700 mAh AA batteries and also Sanyo Eneloops 1900 mAh capacity. The Powerex cells have died 3 years ago while the first generation Eneloops keep going. So you get more bang per buck. Undoubtedly, the capacity has been reduced over the years. Some get hot while charging.

 

I recently got the latest color-coded Eneloops and will see what kind of runtime I get with these.

[dictum9]

BTW, what is that "battery save" feature in the 650T?

[+Walts Hunting]

I think it shuts of the screen and turns it on when you touch it. Without that it times out to dim the screen. That time is settable

[+BAMBOOZLE]

Re: Eneloop XX - it seems they gained runtime (capacity) at the expense of recharge cycles. The lower the capacity, the longer it stays good, and the lower is the self-discharge rate.

 

The higher capacity AA NiMH cells are great if you constantly use them.

About 6 years ago, I got both Maha Powerex 2700 mAh AA batteries and also Sanyo Eneloops 1900 mAh capacity. The Powerex cells have died 3 years ago while the first generation Eneloops keep going. So you get more bang per buck. Undoubtedly, the capacity has been reduced over the years. Some get hot while charging.

 

I recently got the latest color-coded Eneloops and will see what kind of runtime I get with these.

 

I was a huge PowerX fan and have a drawer full......now all I use are the Eneloop 2500's.

The combination of a good MAHA charger and Eneloop 2500's cannot be beat IMO.